Abstract: Apparatus and method for sharpening a cutting tool, such as a kitchen knife. A sharpener has a base unit and one or manual sharpening modules. The base unit has a housing which encloses at least one flexible abrasive disc rotated by an electric motor. Each flexible abrasive disc is adjacent a powered sharpening stage to perform a primary sharpening operation upon the tool. Each manual sharpening module may be removably attachable to the base unit and has a manual sharpening stage that incorporates at least one sharpening element to perform a secondary sharpening operation upon the tool. Each manual sharpening module further has a powered stage guide surface to form a portion of a corresponding powered sharpening stage. When two powered sharpening stages are used, the manual sharpening module(s) can be individually placed between the powered sharpening stages to provide opposing powered stage guide surfaces for each.

Abstract: Apparatus and method for sharpening a cutting tool having a blade portion with a cutting edge, such as but not limited to a kitchen knife. In some embodiments, a powered sharpener moves a flexible abrasive member such as a belt or disc along a neutral plane. A support member contactingly supports a back side of the flexible abrasive member at a medial location along the neutral plane. The support member is positioned adjacent a contact region of an abrasive surface on an opposing front side of the flexible abrasive member against which a cutting edge is brought during a sharpening operation. In some cases, the support member is a stationary or moveable support member such as a pin or roller offset from the contact region. In other cases, the support member is a platen that projects forward to support the contact region.

Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a tool sharpener includes an abrasive medium having an abrasive surface. A stationary tool support guide provides a guide surface that supports a side of the tool during presentation of a cutting edge of the tool against the abrasive surface. A rotatable edge guide has a roller member with a curvilinearly extending outer surface. The roller member is rotatable about an edge guide roller axis to engage, via rolling contact, the cutting edge during the presentation of the cutting edge against the abrasive surface.

Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a powered sharpener has a main drive assembly with an electric motor, and a sharpening assembly with belt support surfaces to provide a routing path for the belt to define first and second belt segments. A first blade guide is configured to position a blade of the cutting tool at a first guide angle to sharpen a cutting edge of the blade against the first belt segment. A second blade guide is configured to position the blade at a second guide angle to sharpen the cutting edge of the blade against the second belt segment. The first and second belt segments may be parallel or non-parallel. As desired, anti-torsion members may be provided to contactingly engage a backing layer of the belt to resist torsional twisting of the belt during sharpening against the first and second belt segments.

Abstract: A tool sharpener has a guide assembly to support a cutting tool adjacent an abrasive medium. A drive assembly advances the abrasive medium with respect to the guide assembly. A control mechanism provides a first control input value to move the medium and achieve a first material take off (MTO) rate during a coarse sharpening operation upon the tool. A second control input value from the control circuit moves the medium to achieve a lower, second MTO rate during a fine sharpening operation. The control mechanism transitions the medium from the first MTO rate to the second MTO rate responsive to a timer mechanism indicating a conclusion of a predetermined elapsed time interval.

Abstract: Apparatus and method for sharpening a cutting tool so as to have enhanced cutting performance. In some embodiments, a tool sharpener is provided having a rigid body with a slot extending therein. A knurl roller is disposed within an internal cavity within the rigid body and mounted for rotation about a selected axis adjacent the slot to facilitate a cold forging operation upon a cutting edge of a cutting tool via insertion of the cutting edge into the slot and retraction of the cutting tool across the knurl roller. An abrasive member is affixed to the rigid body to facilitate a sharpening operation upon the cutting edge by advancement of the cutting edge thereacross.

Abstract: Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.

Abstract: Method and apparatus for sharpening a cutting tool having a blade portion with a cutting edge, such as but not limited to a kitchen knife. In some embodiments, a powered sharpener has an abrasive medium that is advanced by a motor and an edge guide surface adjacent the abrasive medium, wherein the cutting edge of the cutting tool is sharpened by bringing a first portion of the cutting edge into contacting engagement with the edge guide surface and drawing a second portion of the cutting edge across the abrasive medium. A plurality of spaced apart channels are formed in the sharpened cutting edge by contactingly engaging the sharpened cutting edge with a cold forging member with sufficient force to displace portions of the sharpened cutting edge. The channels in the sharpened cutting edge constitute locally deformed, work hardened notches.

Abstract: Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.

Abstract: A multi-rod hand-held sharpener. In some embodiments, the sharpener has a handle with opposing first and second ends, an outer grip surface, and a guide surface adjacent the first end extending at a selected angle with respect to a central axis. A first abrasive rod is adapted to extend from the first end of the handle in a selected direction parallel to the central axis and having a first outer abrasive surface with a first abrasiveness level, the first outer abrasive surface extending at a first non-orthogonal angle with respect to the guide surface. A second abrasive rod is adapted to extend from the first end of the handle in the selected direction and having a second outer abrasive surface with a different, second abrasiveness level. The second outer abrasive surface extends at a different, second non-orthogonal angle with respect to the guide surface.

Abstract: A multi-stage hand-held sharpener. In some embodiments, the sharpener has a handle adapted to be gripped by a hand of a user, the handle extending along a longitudinal axis between opposing first and second ends. A primary sharpening stage is provided in the handle between the first and second ends, the primary sharpening stage having a first abrasive surface extending at a first angle to facilitate a primary sharpening operation by a user upon the tool. An abrasive rod extends from the first end of the handle in a direction parallel to the longitudinal axis. The handle includes a substantially flat guide surface linearly extending from the first end toward the abrasive rod at a second angle, the abrasive rod and the guide surface forming a second sharpening stage adapted to facilitate a secondary sharpening operation by the user upon the tool.

Abstract: Method and apparatus for sharpening a cutting tool. In some embodiments, a sharpener has a guide assembly adjacent a moveable abrasive medium. The medium is advanced at a first speed relative to the guide assembly during a coarse sharpening operation in which a user presents the cutting tool against the medium to shape a side of the cutting tool and generate distended material from the cutting edge (e.g., burrs). The medium is subsequently slowed to a lower, second speed for a fine sharpening operation in which the user presents the cutting tool against the medium to remove the distended material and provide a sharpened cutting edge.

Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a tool sharpener includes an abrasive medium having an abrasive surface. A stationary tool support guide provides a guide surface that supports a side of the tool during presentation of a cutting edge of the tool against the abrasive surface. A rotatable edge guide has a roller member with a curvilinearly extending outer surface. The roller member is rotatable about an edge guide roller axis and is moveable between a deployed position and a retracted position. In the deployed position, the roller member is positioned to engage, via rolling contact, the cutting edge during the presentation of the cutting edge against the abrasive surface. In the retracted position, the roller member is positioned to provide a non-contacting clearing relation with the cutting edge during said presentation.

Abstract: A sharpener for sharpening a cutting tool having a blade portion with a cutting edge, such as but not limited to a kitchen knife. In some embodiments, the sharpener has first and second rollers, with the first roller rotatable about a first roller axis and the second roller rotatable about a second roller axis parallel to the first roller axis. An endless abrasive belt is arranged along a belt path that passes over the first and second rollers to define a planar segment that lies along a neutral plane from the first roller to the second roller. A guide assembly adjacent the planar segment of the belt is configured to contactingly engage the cutting edge of the cutting tool and apply a non-uniform surface pressure to a side of the cutting tool adjacent the cutting edge across a width of the belt.